.menu{
  width: 200px;
  height: 500px;
  border: 1px solid #000;
}
.menu li{
  list-style: none;
  margin-top: 20px;
}

.menuUL{
  display: flex;
}
.menuUL li{
  list-style: none;
  background-color: black;
  color: white;
  margin-left: 20px;
  margin-top: 30px;
}
.menuUL li:hover{
  background-color: red;
}
.rightDiv{
  border: 1px solid black;
  width: 900px;
  height: 500px;
  position: absolute;
  top: 22px;
  left: 252px;
  display: none;
}
table{
  width: 500px;
}
.menu li:hover .rightDiv{
  display: block;
}
